1. Field of the Invention
The present invention is applicable to a doffing and donning machine such as that disclosed in U.S. Pat. No. 3,077,725 and since this patent may be referred to for a more detailed description of such a machine, it is considered unnecessary at this point to insert herein the details of the general aspects of construction and operation of this unit.
This doffing and donning unit as disclosed in the above patent is adapted to be mounted by rollers on a rail fixed to a spinning frame and is designed to move along and in close proximity with a row of spindles supported by said spinning frame. The machine includes adjacently situated and vertically disposed doffing and donning mechanisms which are individually movable in a lateral direction to and away from operating position.
When these mechanisms are in operating position and the machine is being moved along the rail of the spinning frame, the wound or full bobbins are first doffed from their respective spindles and the donning mechanism being adjacently disposed on said machine is brought into operation by continued movement of the machine to don or impale empty bobbins on those spindles from which the doffing mechanism had removed the full bobbins.
2. Description of the Prior Art
The donning mechanism when in operating position is disposed above the row of spindles with only sufficient clearance between the top of the doffed spindles and said mechanism to permit uninterrupted advancement of the machine along the spinning frame. This limited amount of clearance between the spindle and the donning mechanism will cause the upper portion of an undoffed bobbin to come into contact with the donning mechanism to create a jamming condition resulting oftentimes in a bent and damaged spindle.
U.S. Pat. No. 3,321,897 shows and describes one form of a spindle protection device for deactivating the donning mechanism in the event a wound bobbin fails to be doffed from its respective spindle. The device of this patent utilizes a pivotal indicating lever and latching pawl arrangement which are interconnected by a camming member and mechanical linkages. The indicating lever is disposed so as to be engaged by an undoffed bobbin and by means of the camming member and mechanical linkage operatively associated with said lever, the latching pawl arrangement is actuated to release the donning device so that it will retract to an inoperative position.
The distance between spindles on a spinning frame can vary between two-and-one-half and three-and-one-half inches, and the donning and doffing machine is designed so that wound bobbins are being doffed two to three spindles ahead of those spindles on which empty bobbins are being impaled by the donning mechanism. The machine is manually pushed by an operator along the rail of a spinning frame at a speed approximately equivalent to a normal walking pace. The speed at which the machine is moved along the rail of a spinning frame, and the distance between the spindles being doffed of wound bobbins and those impaled with empty ones coupled with the wellknown condition of lost motion and delays which are frequently present in the means for actuating devices that are controlled solely by mechanical means, it has been considered advantageous and desirable to provide a spindle protection device which is effective in deactivating the donning mechanism in a shorter period of time than has been heretofore possible.
The spindle protection device comprising the invention provides a means which instantly transmits an indication of an undoffed bobbin to effect release of the donning mechanism to its inoperative position and eliminates all possibility of an undoffed bobbin from contacting said donning mechanism and the resulting damage described above.